Hmmmm,, I'd say segments. Segments is a little like 'tiles' but in 3d. Imagine that you are making a map at full size then you could say that these 'tiles' 'chops' up the large 'terrain' into smaller pieces.
the larger the entity is the harder it is for the GPU to render it and it can cause some performance issues as would be the case if you'd use a huge entity.
I don't know the hardware specs of the machine running it so I think you should try anyway with your plans. Maybe it works fine and then I'd gladly eat up my words
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